Accuracy of bioelectrical impedance spectroscopy in measuring changes in body composition during severe weight loss.

摘要: BACKGROUND: Bioelectrical impedance spectroscopy (BIS) is an attractive method for measuring body composition because it noninvasive, simple, and cheap. The effect of obesity on the accuracy measurements has been recognized some time, but no conclusive explanations or ways to correct measurement errors have published. We studied weight loss BIS measure changes in fluid volumes during severe loss. Within subjects variable losses fat mass was studied. METHODS: In 10 morbidly obese female who underwent gastric reduction surgery, total water (TBW) extracellular (ECW) were monitored 1 year by deuterium (Deu) bromide (Br) dilution BIS. Measurements performed before operation after 2 weeks, 3 months, year. Extrapolated resistance values (Recw) intracellular (Ricw) used mixture equations calculat...